Microreactor and production method thereof

Abstract

A microreactor is configured to have a metal substrate having a microchannel portion on one surface thereof, a heater provided on the other surface of the metal substrate via an insulating film, a catalyst supported on the microchannel portion, and a cover member having a feed material inlet and a gas outlet and joined to the metal substrate so as to cover the microchannel portion. Since the microreactor uses the metal substrate having a high thermal conductivity and a small heat capacity, the efficiency of heat conduction from the heater to the supported catalyst becomes high, and the processing of the metal substrate is easy to facilitate the production.

The invention claimed is: 
     
       1. A microreactor for obtaining hydrogen gas by reforming a feed material, comprising:
 a first metal substrate including a first surface that includes a first single continuous microchannel portion to carry a catalyst and a second surface, opposite to the first surface, that does not include a microchannel portion, and a first through hole extends through the second surface directly into a first end of the first single continuous microchannel portion; 
 a second metal substrate including a first surface that includes a second single continuous microchannel portion to carry a catalyst and a second surface, opposite to the first surface, that does not include a microchannel portion, the first and second metal substrates being stacked in multi-steps so that the first surfaces where said microchannel portions are formed are oriented in a same direction, and said second metal substrate is provided with a second through hole that extends from a location on the second surface of the second metal substrate that faces a second end of the first single continuous microchannel portion into a first end of the second single continuous microchannel portion for communication between said microchannel portions of the metal substrates in the respective steps; 
 a heater that is disposed, via an insulating film, on the second surface of the first metal substrate where said microchannel portion is not formed; and 
 a cover member having a gas outlet, the cover member being joined to said second metal substrate located at an outermost position of the multi-steps and exposing said second single continuous microchannel portion. 
 
     
     
       2. A microreactor according to  claim 1 , wherein said first metal substrate is one of an Al substrate, a Cu substrate, and a stainless substrate. 
     
     
       3. A microreactor according to  claim 1 , wherein said insulating film is a metal oxide film formed by anodically oxidizing said first metal substrate. 
     
     
       4. A microreactor according to  claim 3 , wherein said metal oxide film is also provided in said first and second single continuous microchannel portions. 
     
     
       5. A microreactor according to  claim 4 , wherein said first and second metal substrates are an Al substrate. 
     
     
       6. A microreactor according to  claim 1 , wherein said heater is provided on the first metal substrate located at an outermost position of the multi-steps, and a heater protective layer is provided so as to cover said heater while exposing electrodes of said heater and an opening of the first through hole of said first metal substrate. 
     
     
       7. A microreactor according to  claim 1 , wherein said metal substrates are in a two-step stacked structure with the two metal substrates, and wherein the first metal substrate includes a first catalyst in the first single microchannel portion to carry out mixing of feed materials, vaporization of a mixed feed material, and reforming of mixture gas, and the second metal substrate includes a second catalyst in the second single microchannel portion to carry out removal of impurities from reformed gas. 
     
     
       8. A microreactor according to  claim 1 , wherein the first through hole extends through the second surface of the first metal substrate directly into the first end of the first single continuous microchannel portion in a direction that is perpendicular to a longitudinal direction of the first single continuous microchannel portion. 
     
     
       9. A microreactor according to  claim 1 , wherein the second through hole extends through the second surface of the second metal substrate directly into the first end of the second single continuous microchannel portion in a direction that is perpendicular to a longitudinal direction of the second single continuous microchannel portion and parallel to the first through hole. 
     
     
       10. A microreactor according to  claim 1 , wherein the gas outlet exposes a second end of said second single continuous microchannel portion.